News Coverage
Toxic chemicals found on lettuce
County stresses no local threat
Published April 28, 2003
Local growers are urging consumers not to panic over a report of lettuce contaminated with trace amounts of perchlorate, a toxic component of rocket fuel.
The report issued Monday by an environmental organization found four contaminated lettuce samples in 22 samples purchased in Northern California supermarkets. But dangerous levels of perchlorate in food have never been established, making it hard to interpret the results of the tiny study, said Monterey County Agricultural Commissioner Eric Lauritzen. He also stressed that lettuce now on the shelves is safe.
"The harvest going on right now is from an area where there isn't a problem," Lauritzen said. "There's no perchlorate in the Salinas Valley."
U.S. Sen. Barbara Boxer on Monday called on the federal government to investigate perchlorate contamination in produce following the release of the study.
''The federal government is already woefully behind in addressing perchlorate contamination in drinking water,'' Boxer wrote in a letter to Food and Drug Administration Commissioner Mark McClellan. ''We need to know if our food is contaminated with this toxic substance and from where this contamination is emanating.''
Boxer is asking that the FDA, the Environmental Protection Agency and the Department of Agriculture investigate the problem.
The Environmental Working Group, which issued the report, bought lettuce for the test in January, when about 80 percent of the lettuce supply comes from Southern California and Arizona. These crops are irrigated with Colorado River water, which is known to harbor perchlorate leached from a former Nevada rocket fuel factory.
The organization refused to disclose the brand names of the lettuce it bought -- which included head lettuce, bagged salads and organic prepackaged greens -- saying it didn't want to spark a food scare.
"This is definitely not the conclusive study, but it's suggestive," said Sonya Lunder, an environmental analyst with the group. "It's hard to make a health recommendation from 22 heads, but it's hard to ignore."
The group said it financed the study to urge the federal government to adopt perchlorate safety standards that address both drinking water and agricultural products. The Environmental Protection Agency is reviewing the report.
The EPA has suggested a preliminary safe level of perchlorate in drinking water at 1 part per billion, about one drop in an Olympic-sized swimming pool. The Environmental Working Group is pushing to have a level 10 times lower.
Perchlorate, a chemical salt, is the main component of rocket fuel. It is also used in highway safety flares, fireworks and auto airbags.
EPA studies show that the toxin impairs function in the thyroid gland. This is especially a concern to pregnant women, because thyroid hormones are critical to fetal and infant brain development.
For the Environmental Working Group, Texas Tech University scientist Todd Anderson analyzed the lettuce samples using a common technique known as ion chromatography.
Of the 22 samples, one a prepackaged mix of organic greens, had 120 parts per billion of the toxin. The other three tainted samples had concentrations between 30 and 60 parts per billion.
Anderson said he could not have detected concentrations lower than 30 parts per billion.
Local growers acknowledge concern over the contamination, but stress that more research is necessary before such studies will be helpful.
"It's hard to tell which levels should be of concern," said Mike Kenter, a spokesman for the Tanimura & Antle produce operation in Salinas. "At this point there's been no standard really set, nor has there been any testing procedure that's been approved."
Food and Drug Administration officials say they are developing better scientific methods to detect toxin levels in food, the Los Angeles Times reported this week. Congress is scheduled to consider perchlorate cleanup legislation in the next two weeks.
"In the meantime," said Commissioner Lauritzen, "we're harvesting lettuce in a part of California where there is absolutely no perchlorate."